X=Y-ZH systems as potential 1,3-dipoles. Part 21 activation of the ZH proton in imines.
作者:Ronald Grigg、Gregory Donegan、H.Q.Nimal Gunaratne、Deirdre A. Kennedy、John F. Malone、Visuvanathar Sridharan、Sunit Thianpatanagul
DOI:10.1016/s0040-4020(01)80037-5
日期:1989.1
Imines, RCH=N-ZH, possessing a range of ZH groups (Z=CHCOPh, CHCOSR, CHCONHR, CHP(O)(OEt)2, 2-CH-pyridyl, 2-CH-thiazolyl, and 9-fluorenyl) undergo thermal 1,2-prototropy generating azomethine ylides stereospecifically. The intermediate azomethine ylides undergo cycloaddition reactions with dipolarophiles either via an endo-transition state or via both endo- and exo-transition states to give polyfunctional
亚胺,RCH = N-ZH,具有一范围ZH基团(Z = CHCOPh,CHCOSR,CHCONHR,CHP(O)(OET)2,2-CH-吡啶基,2- CH噻唑基,和9-芴基)经历热1,2-原生质体产生立体定向的偶氮甲亚胺。中间体偶氮甲亚胺基团通过内过渡态或通过内过渡和外过渡态与偶极亲和剂进行环加成反应,以高收率得到多官能吡咯烷。在某些涉及存在酰胺活化基团的亚胺的实例中,亚胺催化双极性亲和剂的顺式-反式异构化。报道了两个环加合物的X射线晶体结构。